The present invention relates to a safety device for an elevator with an elevator car, which car is movable in an elevator shaft, and a counterweight, which counterweight is movable in the elevator shaft, wherein a speed limiter monitoring the speed of the elevator car or of the counterweight is provided and in the case of excess speed actuates a trigger mechanism stopping the elevator car or the counterweight.
A device for triggering a safety brake, which brake is arranged at an elevator car, with braking wedges is shown in the Japanese patent specification JP 2000219450. A limiter cable of a speed limiter monitoring the speed of the elevator car is connected with a first lever arranged at a first axle. The limiter cable is blocked in the case of excess speed of the elevator car, wherein the first lever sets the first axle into rotational movement due to the movement of the elevator car relative to the limiter cable. A second lever, which is connected with the safety brake and by means of which the rotational movement of the first axle causes the braking wedges of the safety brake to engage, is arranged at the first axle. A third lever, which transmits the rotational movement of the first axle to a second axle arranged at the other side of the elevator car, is arranged at the first axle. The braking wedges of the safety brake of the other side of the elevator car are caused to engage by means of the rotational movement of the second axle. A tension spring connected at one end of the first lever and at the other end with a car frame prevents an undesired engagement of the braking wedges triggered by cable oscillations of the limiter cable.
A disadvantage of this known device resides in the fact that the tension spring fixes the trigger mechanism in the starting setting until the limiter cable overcomes the spring force. A second braking check following the first braking check without delay is not feasible with this trigger mechanism.